Biological desalination of high salt wastewater

The treatment of high salt wastewater is an important environmental protection problem in industrial development.  Comprehensive utilization is an important way to solve the bottleneck of high salt wastewater.  The application of high-salt wastewater reuse technology is an important guarantee to obtain significant economic, environmental and social benefits.

The main sources of high-salt wastewater are as follows: (1) Seawater: it usually comes from the drainage or cooling circulating water in the industrial water use process in coastal cities.  (2) Industrial production: the main source of high-salt wastewater is the drainage produced in the production process of printing and dyeing, refining and chemical, oil extraction, pharmaceutical and salt production enterprises.  (3) Salt-containing domestic sewage: it is mainly derived from seawater utilization, which is used in urban life for fire fighting, flushing roads, flushing toilets and other miscellaneous water that does not directly contact with the human body.  (4) Groundwater with high salt content: Groundwater in some areas has high salt content and large total dissolved solids content.

Biological desalination

This process mainly uses microorganisms to oxidize and decompose organic matter.  Microorganisms can treat and adsorb harmful organic pollutants, and high-salt wastewater can transform a large number of organic matter into inorganic matter after its degradation. The wastewater can be reused in the industrial field through purification. This process method has different advantages of other physical and chemical treatment methods, with stronger environmental protection and safety.  In the face of various kinds of polluted wastewater environment, microorganisms have strong adaptability through variation, good metabolism ability, and can produce specific degradation enzymes to treat all kinds of high-salt wastewater, which has great potential.  For example, biological contact oxidation process has the advantages of anti-toxicity, impact resistance, relatively stable microorganisms, strong volume loading, and can maintain the age of sludge. It is very commonly used as a biological desalination technology.  The hydraulic retention time is shorter than that of conventional activated sludge treatment.

The environmental protection and economy of biological desalination will have a good prospect in the treatment of high-salt wastewater in the future.